Transcript regional transit service - Florida Department of Transportation

DEVELOPMENT OF A GIS-BASED
REGIONAL TRANSIT FEASIBILITY
ANALYSIS AND SIMULATION TOOL
Ram M. Pendyala
Dept of Civil & Environmental Engineering
Univ of South Florida, Tampa
Ike Ubaka
Public Transit Office
Florida Dept of Transportation, Tallahassee
N. Sivaneswaran
S&D Associates, Olympia, Washington
81ST Annual Meeting of the Transportation Research Board
Washington, D.C., January 13-17, 2002
OUTLINE
• Background
• Regional transit planning
• Research objectives and scope
• Definitions for regional transit analysis
• Structure of simulation tool
• Modeling methodology
• RTFAST Software Package
• Conclusions and further research
BACKGROUND
• Mobility needs viewed from a regional perspective
• Land use patterns increasingly dispersed
• Adjoining areas become contiguous regions
• Greater interaction among counties and urban areas
• Social and economic benefits arising from regional
transportation service provision
• Greater access to opportunities
REGIONAL PLANNING
• Regional planning on the rise across the country
• In Florida, virtually all urban areas included in a
“regional” transportation model
• Regional Transportation Organization (RTO) in
Southeast Florida to address “regional” mobility
needs
• Limited regional transit service that crosses
jurisdictional boundaries
REGIONAL MODELS IN FLORIDA
Statewide
Model
Holmes
SantaRosa
Jackson
Escambia
Okaloosa Walton
Nassau
Washington
Gadsden Leon
Jefferson Madison Hamilton
Calhoun
Duval
Baker
Bay
Suwannee
Liberty
Columbia
Wakulla
Taylor
Union
Lafayette
Gulf Franklin
Bradford Clay
St Johns
Gilchrist
Alachua Putnam
Dixie
Flagler
Levy
Marion
Volusia
Citrus
Sumter
Seminole
Lake
Hernando
Orange
Pasco
Brevard
Pinellas
Hillsborough
Polk
Trip Generation
Model Data Sources
Legend
Osceola
IndianRiver
Manatee
Hardee
Okeechobee
Highlands
St Lucie
Sarasota DeSoto
Martin
Charlotte
Glades
Lee
Hendry
PalmBeach
Collier
Monroe
Broward
Dade
Model Types
Urban Model
Regional Model
No Model Available,
Will Develop
Models
District 1 RPM
District 5 RPM
Northeast FloridaRPM
Southeast Florida RPM
Tampa Bay RPM
Treasure Coast RPM
West Florida RPM
Alachua/Putnam Counties
Florida Keys
Leon County
0
25
50 Miles
February 7, 2001
N
REGIONAL TRANSIT SERVICE
• Important component of a regional transportation
system
• Regional transit often calls for major resource
commitments
• Need a simulation tool to help:
• Identify and quantify “regional travel” in a region
• Estimate regional transit service needs based on projected
demand
• Assess feasibility of service
PROJECT OBJECTIVES
• Identify criteria for defining regions, regional travel,
and regional transit service
• Develop methodology to quantify regional travel
flows using existing model databases
• Develop regional transit service analysis and
feasibility assessment model
• Implement model via a user-friendly GIS-interfaced
software package
DEFINITIONS FOR REGIONAL TRANSIT
ANALYSIS
• What is a “region”?
• Analyst may define region of interest for modeling
purposes
• Criteria that may be applied include:
• Multi-county area
• Area covered
• Resident population
• Employment base
• Number of “regional” trips
• Existing model areas
DEFINITIONS FOR REGIONAL TRANSIT
ANALYSIS
• What is a “regional trip”?
• Definition affects estimate of regional travel demand
• Criteria that may be applied include:
• Crosses jurisdictional boundaries
• Trip length (distance and/or time)
• Trip purpose
• Time-of-day of trip
• Origin-destination pair of trip
• Volume of travel between O-D pair
• Trip served by regional transit service
DEFINITIONS FOR REGIONAL TRANSIT
ANALYSIS
• What is “regional transit”?
• Focus is on supply side of transit provision
• Criteria that may be applied include:
• Origin-destination pairs served
• Travel corridors served
• Access and egress opportunities
• Characteristics of trips/users served
• Travel volumes served
STRUCTURE OF DECISION SUPPORT TOOL
Select origin
zones
Define Region:
Zone Structure and
Transportation Network
Run travel model with
existing conditions and
extract trip tables and
skim tables
OR
Run simplified direct
demand model if travel
model databases not
available
Select destination
zones
Specify regional
travel criteria
Select desired trip purposes
and time of day
Quantify regional O-D flows
Select desired area and facility
types for route selection
Identify regional route(s) that
most closely meet specified area
and facility type criteria
STRUCTURE OF DECISION SUPPORT TOOL
(continued)
Identify stops and create
buffers of desired size
Extract socio-economic data and
trip exchanges for each buffer
Run transit demand and supply
model on route database
Obtain estimates of ridership,
frequency, and performance
measures for each route
Analyze desired regional
transit route(s) further
IDENTIFY REGIONAL O-D FLOWS
• User may identify specific zone pairs or ask tool to
identify zone pairs that meet regional travel criteria
• Trip interchanges between zone pairs extracted
from trip tables according to specified criteria
• Allows one to identify potential high volume
corridors that may merit regional transit service
• O-D flow information saved to ArcView database for
analysis and display
IDENTIFY REGIONAL O-D FLOWS
BUILDING REGIONAL ROUTE SYSTEM
• Identify Regional Routes
• Choose area types and facility types of interest
• Select zone combinations that merit connectivity
• May define multiple routes connecting different subsets of
zones
• Routes identified according to shortest path algorithm
available in Network Analyst extension of ArcView
• A regional transport network must be available a priori
BUILDING REGIONAL ROUTE SYSTEM
• Define Stop Characteristics
• Specify stop locations (any node on transport network)
• For each stop, specify a buffer size (geographical
access to transit service)
• For each stop, specify possible destination stops
including those on other routes (via transfer)
• Maximum user flexibility in defining stops
BUILDING REGIONAL ROUTE SYSTEM
BUILDING REGIONAL ROUTE SYSTEM
• Develop Route Database for Ridership Analysis
• Extract socio-economic data for stop buffers
• Determine total available trip market at each stop (from
which regional transit service may derive ridership)
• Example: 100 trips from Zone A to Zone B
• Each stop buffer is 20% of zone area
• Then, trip market @ A = 20% x 20% x 100 = 4 trips
INTEGRATED TRANSIT DEMAND AND
SUPPLY MODEL
• Write socio-economic and trip market data (by stop)
to route database file
• Run transit demand and supply model on route
database
• Estimate ridership potential, equilibrium frequency,
and route performance measures
• Estimates number of boardings by stop
MODEL OUTPUT
• Ridership = number of boardings by stop
• Service = equilibrium service frequency by stop
• Performance measures
• Passenger trips per vehicle revenue mile
• Passenger trips per vehicle revenue hour
• Output provided in table format and appended to
ArcView database for graphical view
• Output provided both at stop and route level
MODEL EQUATIONS
• Equations based on literature review and published
elasticity measures
• System of equations includes:
• Ridership (number of boardings) equation
• Service frequency equation
• Equations refined using Tampa Bay regional route
ridership database
• Can build and use customized equations
MODEL EQUATIONS
(continued)
• Variables in ridership (boardings) prediction model:
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Population
Zero-car households
Retired households
Households with workers
Employment
Service frequency
Route fare
Average parking cost (at destinations)
Presence of local circulator/feeder service
MODEL EQUATIONS (continued)
• Variables in supply (frequency) prediction model:
• Population
• Ridership (boardings)
• Employment
• Boardings estimated as a fraction of total trip market
associated with stop buffer
• Integrated demand and supply model can be used
for ridership prediction and service planning
SOFTWARE PACKAGE
• Software package called RTFAST: Regional Transit
Feasbility Analysis and Simulation Tool
• User-friendly Windows-based software package
• ArcView GIS interface provides strong database
management and graphical capabilities
• Need to have ArcView and Network Analyst
extension to run RTFAST
CONCLUSIONS AND FURTHER RESEARCH
• Developed regional transit feasibility assessment
tool that quantifies regional travel flows
• Help agencies rigorously analyze regional transit
alternatives
• Includes integrated ridership and service planning
model
• Tool offers flexibility for users to define:
• Regional trips and O-D pairs/corridors
• Transit stop locations and buffers
• Customized equations
CONCLUSIONS AND FURTHER RESEARCH
• RTFAST offer ability to account for origin-destination
connectivity of proposed route system
• Several issues for further development:
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Interfaces with travel demand modeling packages
Estimation of latent/induced demand
Greater accounting of transit accessibility
Consideration of unique transit market segments
Consideration of transfer points